The San Francisco 49ers wrapped up their ninth day of training camp practice Sunday and are now gearing up for their first preseason contest this week. Amid some notable injuries, here are some top takeaways from the day's session.

The injury bug has officially bit the San Francisco 49ers, and Sunday's training camp session further reinforced that problem.

Cornerback Richard Sherman, who exited practice early last Friday with a hamstring issue, was later diagnosed with a Grade 1 hamstring strain. Head coach Kyle Shanahan later indicated that the Niners will hold Sherman out for at least a week, meaning he'll miss the team's preseason opener this Thursday against the Dallas Cowboys.

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The 49ers were easing Sherman back into practices anyway, following him being cleared from his 2017 Achilles injury. And while this is a setback, it doesn't appear as if the Niners are overly worried about his availability come Week 1.

Yet San Francisco also lost starting nickel cornerback K'Waun Williams, who appeared to roll his ankle during Sunday's practice and had to be helped off the field. In his place, the Niners gave rookie corner D.J. Reed some extra reps.

Meanwhile, offensive guard Joshua Garnett (knee) continued to be absent from practice. On the positive, Garnett's knee won't need surgery after he banged it against another teammate three days into training camp. But with Garnett locked into a key battle with Jonathan Cooper for the starting right guard spot, it's safe to say the third-year pro needs all the reps he can get between now and the regular season.

Here are the top five takeaways from 49ers training camp, Aug. 5.

Cornerback Depth Will Be a Major Test

Outside Sherman, Williams and Jimmie Ward, who is dealing with a minor hamstring issue, the Niners' depth at cornerback is pretty untested. Second-year cornerback Ahkello Witherspoon is poised to be the team's No. 2 corner opposite Sherman, which is fine. But behind this group, the 49ers primarily have a makeup of first-year defensive backs.

Reed getting some extra reps should help and increase the 2018 fifth-round NFL Draft pick's stock ahead of the regular season. And yet the injuries also mean a lot to other cornerbacks, such as Tarvarius Moore and Tarvarus McFadden.

McFadden, an undrafted rookie, experienced a number of one-on-one losses on Sunday but finished strong with a diving interception off a deflected pass from quarterback C.J. Beathard.

If both Sherman's and Williams' injuries and recovery drag on, the chances for players like Reed and McFadden to make the roster increase significantly.

Jonathan Cooper Is Winning the Battle for Right Guard

Speaking of that injury to Garnett, Cooper managed to see his first 11-on-11 drills during training camp today. Cooper, who was just cleared following an offseason MCL surgery, has done a lot of individual work throughout camp so far. But Sunday's session marked the first time he saw full-team drills.

While Cooper has dealt with serious injuries over his entire career, unlike Garnett, who was primarily a power blocker at Stanford, Cooper does possess the movement skills head coach Kyle Shanahan prizes for his outside-zone blocking scheme.

And as long as Garnett remains out, the chances of Cooper taking over starting duties increase dramatically.

Wide Receiver Trent Taylor Looks Fine

Second-year wideout Trent Taylor also saw his first 11-on-11 drills Sunday after a minor offseason back procedure and starting camp on the PUP list. While he had been working on a number of one-on-one drills earlier in camp after being cleared, the sight of him in full team sessions is a good one.

Taylor finished with 19 third-down receptions for a first-down last season -- tied for ninth most in the NFL and also tied for first among rookies (Cooper Kupp). He was also Pro Football Focus' top-rated receiver on slant routes his rookie season.

The 49ers still aren't practicing a lot of press coverage, which could be the biggest weakness the relatively smallish Pettis will have to overcome this season. And it will be interesting to see how Pettis matches up against some of the bigger, more experienced corners he'll have to face on game day.

For now, however, Pettis' stock continues to soar.

George Kittle Is Primed for a Breakout Season

A year ago, then-rookie tight end George Kittle ended up setting records, and for all the right reasons. His 43 receptions for 515 yards were the most out of any tight end, drafted in Round 5 or later, during the modern football era. And considering a good chunk of those stats came with quarterbacks Beathard and Brian Hoyer, one can only think how those numbers could see a big spike with Jimmy Garoppolo under center.

Kittle has been putting in the extra work, too, staying after practice today to work with Garoppolo and the rest of San Francisco's tight ends.

But the biggest difference might be the level of maturation Kittle now has after his first year at the pro level.

"My head doesn't feel like it's going to explode every single play," Kittle told reporters after Sunday's practice. "It's more of a reaction, not thinking which, in football, is everything. If you have to think, you're already kind of losing. Once you already know, you hear it and it clicks. ... Now you can read the defense and say, 'hey, I can release like this' to help my guy get open."

That's important. And when looking back at how Garoppolo and Kittle connected five times on Aug. 3, including a 25-yard touchdown during the team's red-zone period, one can see how Kittle is primed to have a massive campaign in 2018.

Peter Panacy has been writing about the 49ers since 2011 for outlets like Bleacher Report, Niner Noise, 49ers Webzone, and is occasionally heard as a guest on San Francisco's 95.7 FM The Game. Feel free to follow him, or direct any inquiries to @PeterPanacy on Twitter.

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